Circular knitting machine



Jan. 1, 1935. P. A, BENTLEY Er AL 1,986,317

CIRCULAR KNITTING MACHINE Filed March 17, 1954 2 sheets-'sheet 1 Jan. 1, 1935. L P. A. BENTLEY n AL 1,986,317

CIRCULAR KNI'ITING NACHINE Y Filed Marchrl'?, 19434 2 Shemts-:heef'I 2 MT @7W vPatented Jan. 1, 1935 UNITED STATES CIRCULAR KNI'ITIN MACHINE Percival Arthur Bentley, Y and Carlyle Herbert Wainwright,

Manger, Leicester, England Charles Frederick '-Iliplication March 17, 1934:, Seria'1 No. I716,134 l' In Great Britain June 21,l 1933 11 Claims.

This invention is for improvements in or relating to circular knitting machines and is particularly applicable to, although not limited to, cir-l cular knitting machines of the type that is characterised by having superposed needle cylinders within correspondingcam boxes and means to i produce relative rotation and rotary reciprocation of the cylinders and cam boxes; this type of machine is exemplified in the specifications-of LettersV Patent Nos. 15,008/1900, 24,290/1912 and 171,483. s

In Patent No. 1,870,550 there is described a knitting machine having means for preventing engagement of the'yarn by a sinker hook at a time in the operationof the machine when such engagement is not desired. In the specific form illustrated in said patent, said means comprises a part (designated 28 in said patent) which is pivoted upon the sinker proper, and which-at the appropriate times in the knitting operationis moved relatively to the sinker so' as to lift the yarn over the top of the sinker and td act as a shield for the sinker hook. 1n operation, this means is found to perform very efficiently the duty Vfor which it was designed, but in practice it has proved somewhat diiiicult to manufacture. The sinker and the part or shield which is pivoted upon it are veryA thin (only some few thousandths of an inch in thickness) and have to work within a correspondingly narrow trick in the sinker ring; hence it will be appreciated-that the making of an eiiicient pivotal connection between the sinker and shield calls for an operation of some delicacy. v

' An object of the presentvinvention is to provide means of the kind referred to wherein the need for a pivotal connection as above mentioned is obviated.

In accordance with the present invention, the shield for the sinker hook is constituted by a device which is separate from the sinker proper, vand in the illustrative construction hereinafter described is located, as heretofore, within the same trick as is occupied by the sinker to which it appertains, but is entirely separate from the sinker,v

being maintained in its proper relation to the sinker, by means other than by a direct attachment to the sinker.

(c1. ss-14) y Figure 2 is an elevation of parts indicated in Figure 1;

Figures 3, 4 and 5 show, respectively, a needle, a slider, and a sinker with its shield, in different positions which they occupy during the operation of the machine: Figures 6 and '-7 show, respectively, in side elevation and detached from the machine, a sinkerhook shield according to this invention and -a sinker with which said shield is adapted t0 be associated.

duced by one needle atI a time'until only about onethird of. the half is knitting andl then gradually increased tothe half again. When those needles which are knitting have passed the stitch cam, the machine continues to revolve in thesame direction Vfor some distance and the yarn 14, as indicated in Figure 1, lies round the outside of the stems of the needles 10, 12 vwhich are inthe idle track but 'of course is'not knitted by them.- 'I'he varrow in Figure 1 indicatedlthe direction of rotation of the needle cylinders at this-r time. Qn the reversal of the machine this yarn Iis withdrawn again by'; spring-operated take-up (not shown) until needles in the' knitting track reach the yarn feeder 16 when knittin again takes place in the usual way. l

A source of trouble which has always existed in a greater or less degree' in machines other' than that described in said patent is as follows:-

When a needle has drawn a loop, the sinkers `8 move inwards and hold the yarn in their hooks, and after the last needle (i. e. the needle 18 in the drawings) which knits has drawn its loop 20 the yarn should lie freely outside the idle needles 10, 12, as shown in Figure 1, and above vthe sinkers on the-left-hand side -of those needles,` but the tendency is for these sinkers to continue to take the yarn and to drag it between the idle needles 10, 12 making a waveflike formation of fthe yarn. When the machine reverses, the yarn should be necessary and the action of the sinkers and of the take-up together have a serious eiiect on the yarn, often causing it to break. The :liner the gauge of the machine (and consequently the greater the number of the needlescand sinkers) are closer together and the yarn will not so* readily lie inside the hook of one sinker and Athe greater is this diiiic'ulty, because the sinkers over the top of the next sinker, and also because 5 to act in their usual way, but the first sinker which is not required for knitting is provided with means which definitely lifts the yarn over the top. of the sinker and so causes the yarn to lie freely round the outside of the idle needles so u that it may be readily withdrawn by the take-up on the reversal of the machine. This considerably reduces the damage done to the yarn and permits higher speeds in the knitting of the heel and toe. V

According to the present invention, the means aforesaid for lifting the yarn over the top of the sinker comprises a sinker-hook shielding device which is separate .from the sinker with `which it is associated.

In the construction herein illustrated the sinker-hook shielding device 28 (see Figure 6) is a thin fiat curved blade of a curvature generally similar to that of the sinker 8.(se`e'Figure 7) The device 28 is provided with a shielding surface 32 and with a butt 34 similar to and, aspresently will appear, serving the same purposes as the corresponding parts of the construction illustrated in said patent. In addition the device 28 has a butt 50 which, as shown inFigures' 3, 4 and needle cylinders continue to revolve for some distance in the direction indicated by the arrow in Figure 1 and the yarn 14 is caused to lie against the outer side of the needles 10, 12. The sinker 8 on the left hand side of the needle 18 acts in usual manner to assist in the formation of the loop 20, as its hook is uncovered, the associated device 28 being in the position shown in Figure 3 at this time. But the sinker on the left hand side of the needle l() (as well as the sinkers likewise placed in relation to the needles 12) had its hooke covered when the needle 10 in an earlier stage of the operation was raised by its slider 36. As this slider 36 moved upwardly, its projection 38 engaged the butt 34 of the device 28, turned the device about its inner end and caused its portion- 32 to shield or cover the hook 24 of the sinker as shown in Figure I5. During the continued rotation of the needle cylinders in the direction indicated by the arrow in Figure 1, the s'inker on the left hand side of the needle 10 moves inwardly and the yarn 14 is thereby caused toslide 'over the upper edge of the shielding portion 32 of the device 28 as shown in Figure 4. Continued inward movement of the sinker. finally causes the yarn to pass `on to the top of the sinker hook 24 and at or about vthis time, the,I butt 34 on the dev'ice 28 slides from olf the projection 38 on the slider 36 and the device 28 then drops to the po- 5, is adapted to be engaged by the cam 44 lwhiclr\sition in which it is shown in Figure 3. The hook engages the butt 26 of the sinker 8. noted that the sides 51 of the butt 50 are not mutually parallel but are somewhat inclined to each other. This formation of the lbutt 50permits the device 28 to swing slightly about that one of its ends at which` the butt 50 is located, so

that `the shielding surface 32 on its other end may be moved to cover (Figures 4 and 5) and uncover (Figure 3) the hook 24 of the sinker. The curved pdrtion 52 is taperdsomewhat to permit the device to have this swinging movement in the trick 54 of the sinker ring 42, in which trick the device 28 is located side-by-side with its associated sinker 8.

.The needle-carrying sliders 36 (Figure 2) of the machine which are placed in those tricks which are next to the shielding devices 28 are each provide'd with a small piece 38 which projects from the side of the slider towards the .shielding device 28 so as to be underneath the butt'34 thereon (see Figures 4 and 5). This small piece 38 conveniently is formed by a part of the slider which is `"bent into a position at right angles to the g'enor projections 38 to have any effect upon the' shielding devices 2,8. Consequently, these devices remain in the lower position in which the portions 32 thereof do not cover the hooks 24 of the associated sinkers which are thus enabled to act in their usual manner. When, however, the sliders 36 are raised to the idle track during the knitting of the heel or toe, the projection 38 on -each slider engages the butt 34 on the outer end of the adjacent deviceV 28 and turning that device about its inner end raises the portion 32 of the device to the higher position in which the hook 24 of the associated sinker is covered or shielded.

Figures 1 and 2 are illustrative of a stage in .4 the operation of the machine in which the needles Itwillbe- 24 of-this particular sinker is thus prevented at this stage of the operations from engaging the yarn 14 and dragging it betwen the idle neecues. When the sinker has moved inwardly as described, the butt 34 is clear of the projection 38 on` the slider 36, so that the latter is enabled to have imparted to it a further upward movement which may take place if the slider" is to transfer its needle to the top cylinder.

As shown in Figure 2, it would appear that the yarn 14 lies suiilciently above the sinker` to the left Vof the nedle 10, as not to be likely to be engaged by the hook of that sinker. It should be bornein mind, however, that the sinker hook at this stage is atsome distance outwardly from the yarn and that by the time the needle cylinders have turned to the stage where the sinker hook normally performs its yarn pulling function, the angle which the yarn 14 makes with the horizontal will be less than that shown in Figure 2 with the result that this lower position of the yarn will render the yarn very liable to be engaged by the hook of the inwardly ,moving sinker. Moreover, for the sake of cleamess a very coarse gauge machine has been illustrated in the drawings. 0n a finer gauge machine than that illustrated, the tendency for improper engagement of the yarn by the sinkers is enhanced, since the sinkers lare closer together and therefore are situated closer to the low point of the yarn where the yarn merges into the loop formed by the last operative .needle and sinkers. ,r Although the present invention is particularly applicable in connection with the knitting of heels and toes Awhere a relatively large number of adjacent'nedles are thrown out of action as regards their stitch-forming operation, the invention is equally `applicable in other connections, for instance, fancy work, where it may be but a single needle in any given part of the needle ciry slider for moving said needle, a hooked sinker, a shield separate from the sinker adapted to be moved into shielding Irelation to the sinker hook, a butt on said shield, and a projection on said slider arranged to engage said butt.

2. In a circular knitting machine, a needle, a slider for moving said needle, a hooked sinker, a shield separate from the sinker adapted to be moved into shielding relation to the sinker hook, a butt on said shield, a projection on said slider, arranged to engage said butt, and a cam engaging said sinker and shield for moving said twol parts in company.

f 3. In a circular knitting machine, a sinker ring having a trick therein, a hooked sinker in said trick, a shield in said trick but separate from the sinker and adapted to be moved into shielding relation to the sinker hook, means to move the shield into such shielding relation, and a cam engaging said sinker and shield for moving said two parts in company.

4. A circular knitting machine according to claim 3 wherein thesinker and shieldeach have a butt in engagement with said cam, and the butt of the shield is tapered to permit swinging movement of the shield about said butt into and out of said hook shielding relation.

5. In a circular knitting machine wherein at certain parts of the work the needles of a group of needles cease knitting successively, the combination with such needles, of hooked sinkers associated with said needles, a plurality of yarn engaging elements separate from the sinkers, one located adjacent each needle, said elements being adapted to be shifted toengage the yarn to prevent contact of the yarn with the sinker hooks, and means for shifting successive elements progressively across the said group of needles as the needles are thrown out of action successively, so as always to be in close proximity to a needle at the end of those needlesl of the group which are knitting, and thereby maintain the yarn out of the range of action of the hook of a sinker associated with that needle.

6. In a circular knitting machine wherein at certain parts of the work the needles of a group of needles cease knitting successively, the combination with such needles, of hooked sinkers associated with said needles, a plurality of yarn engaging elements separate from the sinkers, one located adjacent each needle, said elements being adapted to be shifted to engage the yarn to prevent contact of the yarn with the sinker hooks, andmeans movable with the needles for shifting successive elements progressively across the said group of needles as the needles are thrown out `of action successively, so as always to be in close proximity to a needle at the end of those needles of the group which are knitting, and thereby maintain the yarn out of the range of action of the hook of a sinker associated with that needle.

7. In a circular knitting machine wherein at certain parts of the work in the knitting operation the stitch forming function 'of a needle is automatically suspended, the combination with such needle, of a hooked sinker normally co-operating therewith, means separate from the sinker adapted to be positioned to prevent engagement of the yarn with the sinker hook, and means movable with the needle for positioning said flrst named means.

8. -In a circular knitting machine wherein atcertain parts of the work in the knitting operation the stitch forming function of a needle is automatically suspended by moving the needle to inoperative position, the combination with such needle, of a hooked sinker normally cc-operating therewith, means separate from the sinker adapted to be positioned to prevent engagement of the yarn with the sinker hook, and means controlled by movement of the needle to inoperative position for positioning said rst named means.

Y 9. In a circular knitting machine vwherein at certain parts of the work in the knitting operation the stitch forming function of a needle is automatically suspended by moving the needle to inoperative position, the combination with such needle, of a hooked sinker normally ca -operating therewith, means separate --from the sinker'adapted to be positioned to prevent engagement of the yarn with the sinker hook, and means carried with the needle in the movement of the latter to inoperative position for engaging said first named means to position the latter.

10. In a circular knittingmachine, the combination with a needle `and a hooked sinkerl associated therewith in the knitting of yarn into a fabric, of means adapted to ensure that the yarn shall not be engaged by the hook of the sinker, at a time during which in the operation'of the machine, the yarn knitting function of the needle is suspended, said means comprising a shield separate from but-associated with the sinker for closing the sinker hook, and means for moving said shield into shielding relation with said hook.

11. In a circular knitting machine, the combination with a needle and a hookedsinker associated therewith in the knitting of yarn` into a fabric, of means adapted to ensure that the yarn shall not be vengaged by the hook of the sinker, at a time during which in the operation of the machine the yarn knitting function of the needle is suspended, said means comprising a shield separate from the sinker adapted `to prevent the yarn from being engaged by the hook of the sinker, a slider for moving the needle and means operated by said slider for moving said shield into shielding relation to the sinker hook.

PERCIVAL ARTHUR BENTLEY. CHARLES FREDERICK'MANGER. CARLYLE HERBERT 

